Look into the person who owned her last probably had some bad things happening in the field. Try staying with her in the field for a little bit each day to show her your not a threat.
I personally only ride with a whip when I'm riding a lazy pony because sometimes just seeing the whip speeds them up or a light tap on the bum works just as well. Some people say it's cruel to use a whip on ponies after all they have feelings but I think unless you thwack them a light tap is...
I've bee riding for almost 3 years now but awhile back I started to canter, but my instructor rushed me into it. Having a women chasing you with a whip (to make the pony go faster) is very scary. I just about got over the fear when I had a lesson where I got into canter but the pony wasn't...